I have a Yanmar YBH-765 on my kubota B7100. Mine has Yanmar stickers and a Yanmar ID plate with model & serial #'s. However I have found that it was actually built by the Woods company and is actually a Woods BH750. I have no idea how old mine is but yours may be the same as mine. If you go to the Woods web site you can download manuals and you should be able to tell if yours was built by Woods as mine was.
Glad to help. I was pleasently surprised when I figured out the Yanmar backhoe I bought very cheep because the previous owner could not find parts was actually built by Woods.